Wow! My older boys would love that stuff, but it would be impossible to keep it away from all the other kids!
We like outdoors as much as possible, too. Last weekend we had 10-year-old boy guest (his parents went to a F.A. Hayek symposium ... FReepers :-). On Saturday we went to a park that has an obstacle course, with lots of climbing, and ran them around it until they were ready to drop. Everybody in bed by 8:00, and not a peep out of them!
Kind of "borg-like", actually.
We've successfully (nearly) trained ours that, if they do not want things broken or played with by The Small One, they must put them away EVERY time they are done playing with them AND in a location inacccessible or unknown to him. Mostly, we have not allowed "mine only" toys, opting for mandatory sharing of almost everything. This has worked out very well, and each child does have a group of items that we have allowed to be designated "special", which means that they do not have to share them. Once an item is dubbed "special" everyone knows that getting a turn with it is "by permission only, or else".